Hearing fans voice their frustrations is nothing new in football, but rarely do those protests escalate to such a point that matches have to be called off.
Over the years, however, we have seen a handful of matches abandoned because of a range of things, from sit-down protests to all-out brawls which range from the funny to the downright scary.
Here's a look at some of the most notable examples of protests forcing games to be called off.
1. Slavia Prague vs Olomouc (05/05/11)
1,500 Slavia fans stormed on to the pitch before their cup semi-final game with Olomouc in 2011 to protest the club's uncontrollable debts, but they were convinced to leave and let the game go ahead by a bunch of desperate players.
45 minutes later, the fans were back.
When the two teams went off at half-time, supporters rushed to the centre circle, chanting 'We want the truth. Long live Slavia'. There were reports of clashes with riot police, damaged equipment and even an attempt to attack club director Miroslav Platil.
Unsurprisingly, the two teams didn't come out of the tunnel for the second half.
2. Deportivo Tachira vs Atletico Venezuela (19/10/12)
A contender for worst reason to protest right here.
Venezuelan side Deportivo Tachira chose to do away with their normal black-and-yellow home shirt in favour of wearing a pink jersey in support of Breast Cancer Awareness Month in October 2012, but some Neanderthal fans decided that was unacceptable.
A not-small group of fans rushed the field in the 40th minute, chanting the national anthem (of course) and waving the club's normal home shirt in the faces of stunned players.
When the fans refused to leave the pitch, the game had to be abandoned.
3. Blackpool vs Huddersfield (02/05/15)
Having been in the Premier League just four years earlier, Blackpool fans decided they had seen enough of their owners, the Oyston family, as the club were tumbling down the Football League.
Fans had launched fireworks and eggs on to the pitch in a meeting with Reading in April 2015, but a few weeks later, they took their protest to a new level.
Bottom of the Championship when Huddersfield came to town, a group of 2,000 fans protested against Oyston before the game and hundreds kept things going after kick-off, storming the pitch in the 48th minute and refusing to leave.
The group stayed there for over an hour, partying in a conga line as they called for Oyston to walk away, and there were even fans pulling doughnuts on mobility scooters.
4. Leyton Orient vs Colchester (29/04/17)
Here's a weird one.
Leyton Orient fans stormed the pitch late on in April's meeting with Colchester for a sit-down protest against the ownership of Francesco Becchetti, who had overseen a fall down the National League which put Orient on the brink of extinction.
When fans refused to leave, both Orient and the EFL announced that the game had been abandoned, but that was actually just a trick to get all the fans to leave.
Once the stadium was empty, the two teams came back out to finish things up. Quite smart, really.
5. Santos vs Independiente (29/08/18)
Santos' Copa Libertadores tie with Independiente in August 2018 also threw out a weird story.
The two teams drew 0-0 in the first leg, but just hours before the second leg kicked off, it was announced that Independiente had been awarded a 3-0 win from the first game because Santos had used an ineligible player. Midfielder Carlos Sanchez was found to still be under a ban he picked up with River Plate in 2015, despite CONMEBOL's system showing no bans beforehand.
Santos were punished with the 3-0 loss, and fans were livid. They had clashed with police before the game and snuck fireworks into the stadium to launch at the Independiente players.
Percussion grenades were thrown and police started beating the protesters with batons, so the tie was eventually cancelled.
6. Grasshoppers vs Sion (16/03/19)
Swiss side Grasshoppers have dealt with more than their fair share of protests.
The 2018/19 season was littered with fan unrest for Grasshoppers. They had been in the Champions League four years earlier and in the Europa League in 2016/17, but they were on the brink of relegation this time around, and fans weren't having it.
March's meeting with Sion had to be abandoned after fans threw fireworks on to the pitch, but things got really bad a few months later when local rivals Zurich came to town.
With Grasshoppers down 4-0, fans threatened to invade the pitch and eventually managed to corner the squad, demanding they hand over their shirts because they were not fit to wear them.
Shirts were offered up out of fear, and unsurprisingly, Grasshoppers ended up getting relegated.
7. Hoffenheim vs Bayern Munich (29/02/20)
Bayern Munich's trip to Hoffenheim didn't actually get abandoned because of a protest, but it might as well have been.
Late in the game with their team 6-0 up, Bayern fans unveiled a banner criticising Hoffenheim owner Dietmar Hopp, branding him 'a son of a b***h' for trying to break Germany's 50+1 system.
Their protest upset the players, who agreed to leave the field when the Bayern fans would not remove their banner.
The two teams eventually returned but flat-out refused to play, instead kicking the ball around to each other for the remaining 13 minutes.
8. Marseille vs Rennes (30/01/21)
After weeks of peaceful protests, Marseille fans chose to storm the team's training ground in January 2021 to voice their frustration towards the club's ownership and recent form, but things quickly turned ugly.
Defender Alvaro ended up being beaten up and robbed by fans who eventually started throwing hands at riot police who were called in to try break things up.
25 of the 300 fans involved ended up being arrested, and with so much chaos going on, it was decided that the game with Rennes later in the day simply could not go ahead.
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9. Man Utd vs Liverpool (02/05/21)
The sight of Manchester United fans protesting against the club's owners, the Glazer family, is nothing new. Supporters have a long list of reasons to be frustrated with the American owners.
Their anger boiled over in May 2021, shortly after it was revealed that the Glazers had played a significant role in trying to form the Super League and line their own pockets at the expense of the entire sport.
Hours before a meeting with Liverpool, fans arrived at the United stadium to protest and block the team coach from leaving, before they took to Old Trafford to keep the party going. Hundreds of supporters even broke into the stadium and occupied the pitch, calling for the Glazers to leave.
It all seemed peaceful, but outside, violent clashes with police left local authorities with no choice but to postpone the game.